Ramona Diaz’s “The Learning,” a moving film that follows the tribulations and hopes of four Filipina teachers who reluctantly leave their families and come to Baltimore, Maryland because of economic circumstances, will be broadcast across the United States and parts of Canada on Sept. 20 on PBS (Public Broadcasting Service).

The national broadcast premiere will be shown without commercial interruption at 10 p.m. (check local listings).

The film (86 min.), a co-production of CineDiaz and ITVS in association with The Center for Asian American Media, will also stream in its entirety on PBS’ POV website (www.pbs.org/pov/learning) from Sept. 21 to Oct. 21.

POV is American TV’s longest-running independent documentary series and winner of a Special Emmy for Excellence in Television Documentary Filmmaking.

Diaz’s documentary “Imelda” won the 2004 Sundance Film Festival’s Excellence in Cinematography Award for Documentary.

For “The Learning,” a four-year labor of love, Diaz looks at the Philippines’ large pool of trained, highly-motivated and English-speaking teachers, especially in high school math, science and special education.

“These teachers’ poverty-level salaries in the Philippines make them prized recruitment targets for many U.S. school districts, especially those in cash-strapped inner cities like Baltimore,” explains Diaz.

“But while a salary in one of America’s urban districts may be low by American standards, it can be as much as 25 times a teacher’s salary in the Philippines.”

In recent years, there has been a trend of Filipino teachers seeking greener pastures by braving America’s urban schools and their often troubled students.

In Baltimore, 600 Filipino teachers account for 10 percent of the teaching force.

“The Learning” focuses on four Filipina women facing their first year in Baltimore’s schools, as they maintain a long-distance relationship with their families back in their impoverished country.

Diaz follows Dorotea Godinez, Angel Alim, Grace Amper and Rhea Espedido, as the filmmaker captures their individual experiences, their hopes and their daily classroom struggles, while also exposing the tough realities that plague many American public schools.

The making of “The Learning.”

Declining school funding, urban poverty and crime have given these teachers a golden opportunity — and delivered rude shocks as these Filipina teachers are thrust into the heart of America’s educational crisis.

For Dorotea, whose children are almost grown and whose husband is unemployed, the parting is sad but necessary.

For Grace, the opportunity to improve her infant son’s future means separation.

Rhea, whose husband is in prison, declares herself all too ready for something other than the hard life in her native country.

The youngest, Angel, who supports five of her seven siblings, has the most gilded dreams about what America will offer.

In Baltimore, the four women meet welcoming, beleaguered colleagues at the three schools to which they are assigned — Harlem Park Middle School, Renaissance Academy, Lockerman-Bundy Elementary School and Baltimore Polytechnic Institute (one of the highest-ranked public high schools in the state).

They also find disorderly classrooms jammed with mostly African-American students, many behind in their studies and barely motivated to learn.

One of the provocative subtexts of “The Learning,” according to Diaz, is the way poverty has such different effects on young people in the two countries.

“In Baltimore, the kids test the teachers with outrageous behavior, so different from the mannered orderliness of Filipino schoolchildren,” Diaz says.

“The teachers alternate their familial skills and emotional appeals to the students’ better natures with attempts at stern discipline. They find themselves stymied by culturally different classroom rules — in Baltimore, they are not allowed to hug the students freely.”

Diaz continues: “One might expect disaster from such a disparate combination of teachers and students. Yet, slowly, the students’ curiosity gets the better of them and they begin to be impressed by these foreign women who are so determined to teach them. Indeed, the very unfamiliarity of these not-quite-identifiable Asian women helps the black students open up. For the Filipinas, a window also opens: They let go of their cultural expectations and begin to work with the students on American terms.”

The story moves back to the Philippines, where the teachers return for the summer holidays to a hero’s welcome.

As they regale their former colleagues with stories of life in America, they see how their year abroad has changed their families and themselves.

Diaz is a Filipino-American filmmaker whose credits include “Spirits Rising,” a feature documentary about women’s role in the 1986 People Power revolution in the Philippines.

It won the Ida Lupino Directors Guild of America Award, a Golden Gate Award from the San Francisco International Film Festival, a Certificate of Merit from the International Documentary Association, a Student Academy Award and a Gold Apple from the National Educational Media Network.

“Spirits Rising” has been screened internationally and broadcast on public television stations in the U.S. and Australia.

Her documentary “Imelda,” about the former first lady of the Philippines, won the Excellence in Cinematography Award for Documentary at the 2004 Sundance Film Festival and the ABC News Videosource Award from the IDA.

It was released theatrically in the U.S. and the Philippines, screened in more than 50 film festivals internationally and broadcast on PBS’ Independent Lens in 2005.

Her other directing credits include “Don’t Stop Believin’: Everyman’s Journey” (2010), about the band Journey, their new lead vocalist Arnel Pineda and his homecoming in Manila.

She is in development on “Pacific Rims,” based on the book of the same name by Rafe Bartholomew that looks at the Filipino national character through the country’s obsession with basketball.

Prior to directing, she was an associate producer for Cadillac Desert, a PBS series about the quest for water in the American West.

Ramona lives in Baltimore with her husband Rajiv Rimal, an associate professor at Hopkins’ Bloomberg School of Public Health, and daughter Sabina, 14.

She came to the U.S. as a freshman at Emerson College in Boston, Massachusetts, and holds a master’s degree in communications from Stanford University.

Despite her success in the U.S., the diminutive filmmaker says she will stick to making film about the Philippines and the Filipinos — at least for now.

“I make films about the Philippines because it’s what I know,” she points out.

“I have a great advantage when it comes to looking at the Philippines, because, while I was born and raised there, I’ve lived my entire adult life in the United States. I’m both an insider and an outsider, which allows me to have a very distinct point of view.”